Our Mercury mission has begun

The Ariane 5 launch vehicle with the BepiColombo spacecraft on board is at the launch of the Kourou spaceport. If everything goes according to plan, the spacecraft of 6.40 meters and 4.1 tons will reach its destination, the Mercury, in December 2025.

(Photo: AP)

Darmstadt / KourouThe ambitious European-Japanese space mission in Mercury began: a European Ariane 5 launcher was launched on Saturday at 03.35 (CEST) with the BepiColombo space probe aboard the Kourou space station in French Guiana. Both at the spaceport and in the control center of Darmstadt (ESOC) the start of the mission was followed with great interest.

But the spacecraft travel of 6.40 meters and 4.1 tons is only in the beginning. According to the calculations of the European Space Agency Esa, the probe will reach Mercury with its two satellites in December 2025. Until then, researchers will have to intervene repeatedly from Earth. In the coming days, around 80 specialists will oversee the mission at the Control Center (ESOC) in Darmstadt. The CEO of Esa Johann-Dietrich Wörner estimated the total cost of the mission, including development and operations, at around two billion euros. Of these, ESA carries 1.5 billion euros.

The tension will increase again in mid-December. Therefore, for the first time, the ion motors of the probe will be used. If they do not work, the mission may fail. The spacecraft must pass nine planets – once the earth, twice Venus and six times Mercury – above all to slow down. "We have to be careful not to fly in the sun, which means we have to slow down all the time," said Esa Wörner CEO. Every fly of a planet needs intense preparation.

The eponymous of the mission is the Italian mathematician Bepi Colombo (1920-1984), who had calculated the bases for a trajectory to Mercury. If the mission proceeds as planned, two satellites separate from the probe on the target and explore Mercury in different orbits. The MPA satellite of the Esa (Mercury Planetary Orbiter), also called "Bepi", is to investigate the surface. The Japanese satellite MMO (Mercury Magnetospheric Orbiter) – or "Mio" – addresses the magnetic field of the planet. It is about to crash after about 3.5 years on Mercury.

There are eleven cameras and instruments on board the European satellite. Four of these concern German research institutes. These include the Mertis infrared spectrometer from Münster. It should explore the surface of Mercury and help understand the origin of our solar system. At least a year is destined for research, but Bepi could work for a maximum of four years. So the device should burn out, so the Esa.

So far, only two US probes have explored the planet closest to the Sun: "Mariner 10" in the 70s and the "Messenger" spacecraft, which came into orbit around the planet in 2011. The rocky surface of Mercury is – like that of our moon – full of craters. The temperature differences on the planet are extreme. During the day more than 400 degrees are reached, at night it is cold at around minus 180 degrees.